Defender of the Realm #1: Defender of the Realm by Mark Huckerby (author) and Nick Ostler (author) (UK edition)

Alfie thought he knew his destiny. He didn’t know the half of it.

Fourteen-year-old heir to the throne, Alfie, didn’t expect to be King so soon. He DEFINITELY did not expect to be DEFENDER OF THE REALM, a legendary superhero, fighting a secret, centuries-long battle to protect the nation from monsters and super-villains.

An ordinary girl, Hayley Hicks, finds herself fighting alongside Alfie in a desperate struggle to stop a fearsome new enemy, the Black Dragon.